Schedule: a typical Thursday (the flights of Jul 30, 2026, re-dated). Real flights replace these once the FAA publishes them, usually about a day ahead.
ALLEGIANT · FLIGHT G4 571
SCHEDULED · TYPICAL SCHEDULE
Thursday, October 1 Today
G4 571 · BOS → GRR
departs 9:18 AM ET · arrives 11:31 AM ET
Forecast issued Thu 10:00 AM ET · 1h after departure
Watch this flight
Other days
Today
Sun 10/4 13%
Odds over time
Arrive at GRR more than 15 minutes late?
15%
chance · ±1 pts
+0 pts · 24h
HOW SURE WE ARE
Very high. The odds now come almost entirely from live conditions.
Arrive 15+ late
15%
Leave 15+ late
11%
Arrive 1h+ late
5%
Cancelled
<1%
WEATHER FORECASTS
LIVE
IN THE AIR
0%
10%
20%
30%
40%
2.8d
2d
1d
12h
6h
Departs
Lands
Arrive at GRR more than 15 minutes late?
Calm-weather odds: 16% · changed +0 pts in 24h
+0 pts
15%
Yes 15%
No 85%
Leave BOS more than 15 minutes late?
Calm-weather odds: 11% · changed +0 pts in 24h
+0 pts
11%
Yes 11%
No 89%
Arrive at GRR more than an hour late?
Calm-weather odds: 5% · changed +1 pt in 24h
+1 pt
5%
Yes 5%
No 95%
Cancelled?
Calm-weather odds: <1% · changed +0 pts in 24h
+0 pts
<1%
Yes <1%
No 99%
How late will it get to GRR?
On time or early
84%
15–30 min late
6%
30 min–1 hour late
4%
1–2 hours late
3%
Over 2 hours late
2%
Cancelled
<1%
Gate arrival compared with the scheduled arrival. The ranges add up to 100%.
What’s moving the odds
↑
Cloud base down to 600 ft, visibility down to 2 mi, 0.8 in of rain forecast at GRR that day
↑
G4's recent on-time record
↑
BOS is prone to delays
↓
GRR usually runs smoothly
↓
Mostly benign weather forecast at BOS
Weather at each end
BOS (origin)
Gusts 17 kt Ceiling none (clear) Visibility 10+ mi Precip none
GRR (destination)
Gusts 20 kt Ceiling 600 ft Visibility 2 mi Precip 0.78 in
How this resolves
Yes if the gate arrival is more than 15 minutes after the scheduled arrival. Cancelled or diverted flights resolve N/A.
Every question here is display only — there is no betting or money involved. Gate times come from the airline; a cancellation resolves only the “Cancelled?” question, and a diversion voids the delay questions.